RMfixcov is a user-defined covariance according to
the given covariance matrix.

It extends to the space through a Voronoi tesselation.

Usage

1
2

Arguments

scale, Aniso, proj,var

optional arguments; same meaning for any
RMmodel. If not passed, the above
covariance function remains unmodified.

M

a numerical matrix defining the user-defined covariance for a
random field; The matrix should be positive definite, symmetric and
its dimension should be equal to the length of observation or
simulation vector.

x,y,z,T,grid

optional.
The usual arguments as in RFsimulate to define the
locations where the covariates are given

raw

logical. If FALSE then the data are interpolated. This
approach is always save, but might be slow.

If TRUE then the data may be accessed when covariance
matrices are calculated. No rescaling or anisotropy definition
is allowed in combination with the model. The use is dangerous,
but fast.

Default: FALSE (outside mixed models)

norm

optional model that gives the norm between locations

Details

The covariances passed are implemented for the given locations.
Within any Voronoi cell (around a given location) the correlation is
assumed to be one.

In particular, it is used in RFfit to define neighbour or network structure in the data.

Value

RMfixcov returns an object of class RMmodel

Note

Starting with version 3.0.64, the former argument element
is replaced by the general option set in
RFoptions.